Not really. Not requiring functions and macros before calling them is a bug in fsharp-mode. Whether or not 'cl should be provided as the default is another issue all together. The reality is that if you customize your emacs in any significant way, you'll probably load something that requires 'cl at runtime. However anything that makes it into GNU Emacs must not require 'cl at runtime. This is the current policy, but lots of people disagree with it.